Network device and method for providing content compatibility between network devices having different respective digital rights management methods

A method for providing content compatibility between a first network device and a second network device, the method comprising:

• (a) exchanging security program lists between the first network device and the second network device, wherein a first device has a first security program list corresponding to a first digital rights management method and wherein a second device has a second security program list corresponding to a second digital rights management method which is different from the first digital rights management method;
• (b) comparing the first security program list with the second security program list based on the exchanged security program lists;
• and
• (c) installing a security program required for using content of the second network device and the first network device on the first network device and the second network device respectively, according to the comparing;
• wherein (a) comprises transmitting information on an address of a security program server providing the security program registered in the first security program list and information on an address of a security program server providing the security program registered in the second security program list to the second network device and the first network device respectively, together with the first security program list and the second security program list during the exchange.